In communications or storage networks, it is desirable to test network components. One method for testing network components involves using a network test device to send simulated data packets to the communications or storage network element under test and monitor the response of the device to the tests packets. In order to simulate real-world events, it is necessary to change parameter values in the test packets. For example, packet headers often carry sequence numbers, and to accurately simulate some network protocols, it is necessary to change the sequence numbers in successive packets in a stream of packets transmitted to the device under test. Other values that it may be desirable to change in successive packets include source and destination addresses, quality of service parameters, and packet payloads.
The values that are defined by a user or a test application and inserted in a packet are referred to herein as user defined field (UDF) values. A list of user defined fields for a stream of packets relating to an endpoint is referred to herein as a value list. A group of packets related to the same transaction or endpoint is referred to as a flow. For example, in a telecommunications network, a flow of packets may represent packets transmitted from a network access node, such as an eNode B, to another node, such as serving gateway. A group of flows is referred to herein as a stream.
Generating test packets involves reading value lists from memory to construct each packet. The number of memory accesses increases with the number of packets and the number of streams being generated. As a result, memory access bandwidth can become a bottleneck.
One possible solution to the memory access bandwidth problem is to use high bandwidth static random access memory (SRAM) to store the value lists. However, SRAMs are expensive. To reduce memory costs, it may be desirable to use dynamic random access memory (DRAMs) to store the value lists. However, the DRAMs are slow when compared to SRAMs, particularly when it comes to random access.
Accordingly, in light of these difficulties, there exists a need for methods, systems, and computer readable media for generating test packets and network in a network test device using value list caching.